1. Field of the Invention
The present invention relates generally to devices for reducing the amount of air drag on a moving vehicle, and more particularly but not by way of limitation, to the devices for reducing the amount of air drag experienced in a gap defined between a tractor and a trailer of a conventional tractor-trailer combination truck.
2. Description of the Related Art
It is well known that a vehicle, such as a conventional tractor-trailer combination truck having a substantially flat surface along the back of the tractor and a substantially flat front surface along the trailer, experiences a significant amount of air drag in the gap defined between the tractor and trailer while traveling along a road or highway. The passage of the vehicle through the atmosphere creates an area of low pressure in the gap that causes drag on the vehicle and increases both the rate of fuel consumption and the amount of pollution output.
A number of devices have been developed to reduce air drag experienced in the gap between a tractor and trailer. Examples of such devices are contained in the following patents: U.S. Pat. No. 7,374,229 issued to Noll and Sadler; U.S. Pat. No. 6,846,031 issued to Wong et al.; U.S. Pat. No. 6,932,419 issued to McCullough; U.S. Pat. No. 5,190,342 issued to Marlowe et al.; U.S. Pat. No. 4,904,015 issued to Haines; U.S. Pat. No. 4,746,160 issued to Wiesemeyer; U.S. Pat. No. 4,688,841 issued to Moore; U.S. Pat. No. 4,685,715 issued to Hardin; U.S. Pat. No. 4,518,188 issued to Witten; and U.S. Pat. No. 4,036,519 issued to Servais et al.
A need exists for devices that reduce drag on a vehicle particularly drag experienced at the gap defined between a tractor and a trailer of a conventional tractor-trailer combination truck. Devices that reduce the rate of fuel consumption and/or pollution output of the truck would be particularly desirable. The present application provides these and other advantages as will be apparent from the following detailed description and accompanying figures.